Cold agglutinins in cardiac surgery: management of myocardial protection and cardiopulmonary bypass.

Cold agglutinins are of unique relevance in cardiac surgery because of the use of hypothermic cardiopulmonary bypass (CPB). Immunoglobulin M autoantibodies to red blood cells, which activate at varying levels of hypothermia, can cause catastrophic hemagglutination, microvascular thrombosis, or hemolysis. Management of CPB and myocardial protection requires individualized planning. We describe a case of aortic valve replacement in a patient with high titre cold agglutinins and a high thermal amplitude for antibody activation. Normothermic CPB and continuous warm blood cardioplegia were successfully used.